1. Field of the Invention
The invention relates to a seal used for an electric connector having a part protruding outwardly through an opening formed at a wall of a casing, the seal filling a space formed between an outer surface of the part and an inner surface of the opening. The invention relates further to a method of attaching the seal onto the casing.
2. Description of the Related Art
A kind of an electric connector is housed in a casing having a wall formed with an opening, and causes a part thereof to protrude outwardly through the opening. The electric connector is mechanically and electrically connected to a second electric connector through the part protruding outwardly through the opening. In particular, an electric connector to be equipped in an automobile is designed to include a seal to be sandwiched between the part and the opening in order to enhance waterproofness.
FIG. 10A is a perspective view of the electric connector suggested in Japanese Patent Application Publication No. 2009-9845, and FIG. 10B is a cross-sectional view of the electric connector.
As illustrated in FIG. 10B, the electric connector 1000 is mounted on a circuit board 1002 fixed in and to a casing 1001, and is mechanically and electrically connected to a second electric connector (not illustrated) through an opening 1003 formed at a wall of the casing 1001.
A cover 1004 is attached to the casing 1001 through the opening 1003. The cover 1004 includes a cylindrical portion 1008, a flange portion 1010 extending outwardly from an edge of the cylindrical portion 1008, and a seal 1009 sandwiched between the flange portion 1010 and the casing 1001. An electrically insulative housing 1006 (see FIG. 10A) holding therein contacts 1005 through which the electric connector 1000 is electrically connected to the second electric connector (not illustrated) is inserted into the cylindrical portion 1008 with a seal 1007 being sandwiched therebetween.
The electric connector 1000 illustrated in FIGS. 10A and 10B is designed to include the seals 1007 and 1009. The seal 1007 fills a space to be formed between the cylindrical portion 1008 and the housing 1006 inserted into the cylindrical portion 1008, and the seal 1009 fills a space to be formed between the flange portion 1010 and the casing 1001.
Thus, the conventional electric connector 1000 has to include the two seals 1007 and 1009 in order to have waterproofness, resulting in that the number of parts in the electric connector 1000 is unavoidably increased, and the resultant electric connector 1000 has a problem of high fabrication cost.